Fractions in octal (base 8) notation can be expressed exactly in decimal notation. For example, 0.75 in octal is 0.963125 (7/8 + 5/64) in decimal. All octal numbers of n digits to the right of the octal point can be expressed in no more than 3n decimal digits to the right of the decimal point.
Write a program to convert octal numerals between 0 and 1, inclusive, into equivalent decimal numerals.
The input to your program will consist of octal numbers, one per line, to be converted. Each input number has the form 0.d_1d_2d_3 ... d_k, where the di are octal digits (0..7). There is no limit on k.
Your output will consist of a sequence of lines of the form 0.d_1d_2d_3 ... d_k [8] = 0.D_1D_2D_3 ... D_m [10]
where the left side is the input (in octal), and the right hand side the decimal (base 10) equivalent. There must be no trailing zeros, i.e. D_m is not equal to 0.